Under which conditions is it illegal to pass another vehicle?

Passing another vehicle is considered illegal under specific conditions that prioritize safety and traffic flow. In no-passing zones, typically marked by solid lines on the road, it is illegal to overtake another vehicle due to the potential hazards, such as curves, intersections, or pedestrian activity. Similarly, if the vehicle in front is stopped at a crosswalk or intersection, it indicates that there may be pedestrians or other vehicles potentially in danger, which makes passing not just dangerous, but also unlawful.

These regulations are in place to ensure the safety of all road users, including pedestrians, cyclists, and other motorists. In contrast, passing when a vehicle is moving at a speed below the limit, during daylight hours with good visibility, or when the road is clear could be legal, provided that it is done in permitted zones and under safe conditions. However, these scenarios do not excuse passing in areas where it is explicitly prohibited for safety reasons. Therefore, the correct answer embodies the critical legal stipulations that define when passing is not allowed.